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Mythbusters

Nuclear is a subject that has generated its fair share of myths throughout the years. An important part of the Canadian Nuclear Safety Commission's (CNSC's) mandate is providing factual information that helps people understand nuclear science and its effects on people.

This section aims to dispel some of the most common misconceptions about nuclear technology and its applications in areas such as:

The CNSC does not promote the use of nuclear technologies or materials – rather, it regulates their use to protect the health, safety and security of Canadians as well as the environment. The CNSC respects Canada's international commitments on the peaceful use of nuclear energy.

Radiation and health

Myth

Accidents involving nuclear energy are responsible for more deaths than accidents involving other energy sources.

Fact

Nuclear power is one of the safest sources of energy. The number of fatalities involving accidents at nuclear power plants is lower, and in some case much lower, than similar figures for hydro, natural gas, oil and coal.

Myth:

Fact:

MRI machines do not use ionizing radiation. The technology uses a large, powerful magnet combined with a radio frequency to create an electromagnetic field that constructs an image of the body.

There are other forms of medical imaging that use nuclear substances, like isotopes, to obtain images of the body. Many hospitals and health care facilities in Canada deliver isotopes to specific areas of the body and use positron emission tomography (PET) scans to generate images of tissues and organs.

Nuclear medical imaging is used in almost 100 different diagnostic procedures in Canada, and every major organ system can be imaged using these techniques. All imaging procedures that use nuclear substances are required to be carried out under the guidance of a qualified medical practitioner to ensure they are used safely. The amount of radiation that a patient is exposed to is monitored and controlled by a team of health professionals trained in conducting these specialized tests.

Myth:

Fact:

Meta-analysis is an analytical technique designed to combine and summarize the results of multiple studies to increase the sample size and the statistical power to study the effects of interest. It could be a powerful tool when used properly, but it is not always an appropriate choice and can lead to misleading results.

Meta-analysis studies conducted by Baker and Hoel (2007), Mangano (2008) and Kaatsch (2008) – the KiKK study – each claim to have found elevated rates of leukemia for children living near NPPs. The CNSC joins the scientific community in challenging the results of these studies for misuse of the meta-analysis approach. The following are examples of the weaknesses in these studies:

Baker and Hoel (2007) themselves noted that they could not establish a causal relationship between risk of leukemia and distance to an NPP. The study was criticized for selection bias and for combining different age groups, types of nuclear facilities and distances.

The Mangano (2008) study was rejected, for among other things, an inadequate sample size, no population control and the omission of data that did not support the conclusion.

For the KiKK (Kaatsch, 2008) study, there is no support for a causal relationship between leukemia and NPPs (SSK, 2008) and similar studies conducted in France, Britain and Switzerland did not find a relationship between distance from an NPP and childhood leukemia (Laurier et al., 2008a, Bithell et al, 2008, 2010, Spycher et al., 2011).

Myth:

The amount of cesium-137 contained in a check source is dangerous.

Fact:

A check source is a sealed source containing a small, very low-risk quantity of nuclear substance
(like cesium-137) typically used to determine if radiation detection equipment is functioning correctly prior to use.
The source itself is about the size of a head of a pin, inside a sealed container no bigger than a loonie.
It is designed to be safely handled by hand. The amount of radioactivity in a low-level radiation check
source is approximately the same as that found within household smoke detectors.

Myth:

Because polonium in cigarettes is known to be cancer causing, the polonium-210 (Po-210) contained in uranium will cause cancer in uranium workers and the public living near mines.

Fact:

Uranium workers and the public are not at risk from polonium-210 (Po-210) from uranium mining.

Po-210 is a radioactive substance that can be found naturally in small quantities in our bodies and in the environment. While it is a decay product of uranium, it is very rare, and it does not accumulate in the environment around mine sites.

Modern controls and strict radiation protection programs ensure radon and radon progeny (including Po-210) are continuously monitored and controlled in today's uranium facilities. Studies and monitoring have shown there are no significant impacts to the health of the public living near uranium mines and mills.

As for the link to smoking, Po-210 is one of the over 70 known carcinogens found in tobacco smoke. Together, they substantially increase the risk of lung and many other types of cancer, and other illnesses (such as heart disease, stroke and respiratory illnesses).

Myth:

Even one becquerel represents a health risk.

Fact:

One becquerel (Bq) does not represent a measurable health risk. It equals one radioactive decay (or disintegration) per second of any radionuclide and is part of a natural process. In fact, most things we eat and drink contain naturally occurring radioactive elements, like potassium and carbon. For example, 250g of red meat and 250g of bananas naturally contain 28 Bq and 33 Bq of potassium-40, respectively.

Myth:

One becquerel in a woman's ovaries can cause birth defects.

Fact:

One becquerel (Bq) does not represent a measurable health risk, and will not cause birth defects. It equals one radioactive decay (or disintegration) per second and is part of a natural process. Studies on nearly 30,000 children of the A-bomb survivors (who were exposed to relatively high levels of radiation) over three generations have shown no increased risk of adverse hereditary effects, such as birth defects, associated with their parents having been exposed.

Myth:

A becquerel is like a gun shot to the body.

Fact:

One becquerel (Bq) does not represent a measurable health risk. It equals one radioactive decay (or disintegration)
per second of any radionuclide and is part of a natural process. In fact, we experience nearly
90,000 of these disintegrations every day as the natural uranium in our bodies decays.

Myth:

When a large number of people receive a small dose of radiation, often referred to as a "collective dose", some of those people will develop cancer from that radiation exposure.

Fact:

The quantity "collective dose" is often misunderstood and misused.
Simply put, it refers to the amount of radiation received by a group of people.
It is calculated by adding all individual doses in an exposed population over a given period of time.
It is a useful tool for radiation protection purposes, but its function is limited.
It should not be used for predicting disease from radiation exposure.

Myth:

The KiKK and other German studies have demonstrated that there is a higher rate of childhood leukaemia in populations living close to nuclear power plants.

Fact:

These studies have found groups, or clusters, of childhood leukemia near nuclear facilities, but clusters have also been found in areas where there are no nuclear facilities.

These studies have not been able to relate the clusters to the dose of radiation emitted by the facilities. Since childhood leukaemia is thought to be caused by several factors, other factors may have been responsible for the observed results.

Myth:

People in Port Hope are sick as a result of exposure to historical low-level radioactive waste.

Fact:

Port Hope residents are as healthy as the rest of the Canadian population.

This has been demonstrated by several scientific, peer-reviewed studies conducted over many decades by reputable and independent bodies.

The CNSC recently assessed findings from more than 30 environmental studies and 13 peer-reviewed epidemiological studies. It published a synthesis report that was presented during open houses held in the community.

Findings were compared with 40 international epidemiological studies on similar populations and the conclusion was clear: the health of Port Hope residents is no different than that of other Canadians.

Nuclear power plants

Myth:

There is no way to calculate the odds of an accident occurring at a nuclear power plant and what the consequences would be.

Fact:

The nuclear sector uses a powerful tool called probabilistic safety assessment (PSA) to assess the consequences and likelihood of different types of accidents, whether they are initiated by external events (like earthquakes or floods), internal events (such as system malfunctions) or human error. In conducting such assessment, specialists consider all potential accident sequences and look at the performance of the safety systems that need to operate to prevent reactor damage. Specialists also assess the measures in place to limit the consequences of any reactor damage. PSA results are valuable because they confirm the safety of the facilities' design and identify potential areas for improvement.

Myth:

Nuclear power plants can explode like nuclear bombs.

Fact:

A nuclear power plant cannot explode like a bomb. Nuclear bombs are completely different from reactors. Although both use fissile materials, the materials are not alike and are used in very different ways. The fuel in CANDU reactors is natural uranium. To produce a nuclear bomb, highly enriched uranium or plutonium must be used. Natural uranium contains about 0.72 percent of uranium 235. Highly enriched uranium contains at least 80 percent of it. Furthermore, in commercial reactors, nuclear fission is controlled in a system built to make sure the nuclear reaction is controlled. Nuclear bombs are specifically designed to produce uncontrolled fission leading to an explosion.

Myth:

CANDU reactors are dangerous due to their power coefficient of reactivity.

Fact:

The power coefficient of reactivity of CANDU reactors does not pose a significant risk. Consistent with Canadian nuclear safety requirements, nuclear power plants must have an appropriate combination of inherent and engineered safety features incorporated into the design of the reactor safety and control systems. A reactor design that has a positive power coefficient of reactivity is quite acceptable provided that the reactor is stable against power fluctuations, and that the probability and consequences of any potential accidents that would be aggravated by a positive reactivity feedback are maintained within CNSC-prescribed limits. These are known safety issues that have long been addressed by the CNSC's regulatory and safety regime.

Myth:

Tritium levels measured in the drinking water of communities near Canadian nuclear facilities pose a health risk.

Fact:

Tritium levels found in the municipal drinking water of these communities are well below national and international minimum safety standards, and below 20 Bq/L. Read our information update on tritium in drinking water for more details.

Myth:

CANDU reactors produce more plutonium than other reactors.

Fact:

CANDU reactors produce only half as much plutonium by discharged fuel mass as light-water reactors.

Myth:

There is no solution for the disposal of spent nuclear fuel.

Fact:

Currently, all spent nuclear fuel in Canada is stored in safe, engineered facilities designed for short- to mid-term storage. The Nuclear Waste Management Organization (NWMO) has begun a dialogue with the Canadian public to collaboratively develop and implement a management approach for the long-term care of Canada's used nuclear fuel that is socially acceptable, technically sound, environmentally responsible and economically feasible.

Uranium mining and processing

Myth:

Uranium exploration causes dangerous levels of radiation to be released.

Fact:

Typical uranium exploration methods, such as drilling small core samples, pose a negligible to zero risk of increasing exposure to radiation, including radon.

Uranium mining exploration is governed provincially and does not require a CNSC licence.

Myth:

Uranium mines and mills increase radon levels in the environment.

Fact:

Studies have shown that uranium mining and milling activities do not increase radon levels in the environment away from the mine site. The level of radon near uranium mines is similar to natural radon levels monitored in background locations. Radon exposure to members of the public from CNSC-regulated activities is virtually zero.

Myth:

Uranium mines and mills make communities sick.

Fact:

Studies and monitoring have shown that there are no significant impacts to the health of the public living near uranium mines and mills. Human exposure to radon and radiation from modern uranium mining is very low and does not increase the risk of cancer.

Myth:

Uranium miners are exposed to dangerous levels of radiation

Fact:

The CNSC regulates radon and radon progeny in Canada's nuclear facilities to protect the health of uranium workers and the public. Concentrations of radon in uranium mines and mills and uranium processing fuel fabrication facilities are strictly controlled and must be monitored. Controls include sophisticated detection and ventilation systems that effectively protect Canadian uranium workers. The average dose for workers at uranium mines and mills in 2007 was about 1 millisievert (mSv), significantly below the regulatory nuclear energy worker limit of 50 mSv per year.

Myth:

Tailings from uranium mines will remain highly toxic for millions of years and contaminate groundwater.

Fact:

The safe long-term management of waste rock and uranium mill tailings is an important aspect of the licensing process for uranium mines and mills. Techniques have been developed to safely contain this waste from the environment by using natural and/or man-made barriers to control contact between the tailings and groundwater. Tailings are stored and monitored in tailings management facilities, such as tailing ponds or mined-out open pits that are rigorously engineered for long-term storage and stability.

Myth:

Uranium mining and processing are linked to stillbirths, birth defects and cancers.

Fact:

Uranium mining and processing activities do not cause stillbirths, birth defects or cancer in humans or animals.

Natural uranium that is removed from a mine and processed into fuel for nuclear reactors simply does not pose such risks.

Natural uranium is only mildly radioactive. If absorbed in large quantities, its main health risks relate to kidney damage.

However, the public is not exposed to any levels that could cause kidney damage as a result of uranium mining and processing activities.

Myth:

Effluents from operating mines and mills contain several contaminants, such as selenium and molybdenum, that harm fish and other animals.

Fact:

The CNSC ensures groundwater, streams, lakes and rivers downstream of operating uranium mines and mills are safe for people, plants, fish and other animals.

Cumulative monitoring programs in Northern Saskatchewan, where all of Canada's operating uranium mines are located, have confirmed that contaminant levels outside operating mining and milling sites are barely detectable and do not pose a risk for the wildlife.

Many readily available water treatment technologies are used to reduce to safe levels potentially harmful contaminants before effluents are released to the environment.

About historic mine sites – The CNSC and provincial and territorial governments control and monitor releases from mining sites that were built and operated several decades ago.

Most historic mines sites have undergone remediation at this point and the ones that have not are currently under assessment.

The CNSC has since applied lessons learned from the past.

As a result, it has established environmental regulations and programs that are more stringent than any of the other mining sectors in Canada.

Myth:

Acid drainage at operating and old mining and milling sites is an important problem threatening waterways.

Fact:

There are no acid drainage releases at operating mining and milling sites. All releases are controlled and monitored, and do not pose a risk to our waterways.

Modern industrial techniques neutralize the acidity of tailings. Tailings ponds are also designed to minimize any potential acidification.

As part of the decommissioning process, old mine sites have been evaluated and adequate measures have been or will be implemented to protect the environment against potential acid drainage.

Myth:

There are no mines or uranium processing facilities near populated areas and therefore no way of knowing if these facilities are harmful to human health.

Fact:

There are several uranium processing facilities near Port Hope and Blind River, Ontario. Decommissioned uranium mining sites in Northern Ontario are also located near populated areas.

Studies carried out over several decades have repeatedly demonstrated that people who live near these facilities are as healthy as the rest of the general population.

Studies carried out around uranium processing sites in other countries have provided the same conclusion.

The same is true of people who live near nuclear power plants.

Myth:

Fish, game and fruits harvested near operating uranium mines and mills are unsafe to eat.

Fact:

It is completely safe to consume fish, game and fruit from regions near operating uranium mines and mills.

Ongoing monitoring has confirmed that releases near uranium mine and mill sites are barely detectable.

About historic mine sites – Some restrictions apply today to fishing in lakes located on historical mining and milling sites.

Those sites were developed at a time in the 1950s when environmental regulations and programs were non-existent, which is very different from the comprehensive oversight in place today.

Myth:

Fact:

The CNSC ensures adequate measures are in place to minimize possible impacts on traditional activities in areas where uranium mining takes place.

In some cases, trappers have continued to trap and even live on CNSC-licensed properties for the duration of the uranium mine operations.

In Northern Saskatchewan, where all of Canada's active uranium mining facilities are located, Aboriginal groups and communities are visited and consulted at various steps of a project's life.

These groups provide valuable input by sharing traditional knowledge and identifying valued plants, animals and traditional activities. This helps the CNSC ensure any potential impacts are eliminated or minimized.

Aboriginal groups also actively participate in collecting samples that are used to conduct environmental monitoring.

Myth:

Aboriginal traditional knowledge and ways of life are ignored when a new uranium mine or mill is designed and its potential environmental impact is assessed.

Fact:

Aboriginal groups are consulted during all phases of nuclear projects, which include new uranium mines and mills, and they are encouraged to participate in the planning.

Before these projects proceed, Aboriginal rights are always considered.

Myth:

Uranium mining and processing pose a serious health risk to workers and those who live near facilities where these activities take place.

Fact:

Present-day uranium workers and people living near the facilities are as healthy as the general Canadian population.

The CNSC oversees stringent programs to control exposure to radiation and chemical agents, and address any potential health risks to workers.

As a result, members of the public are not exposed to any levels of contamination that could pose health risks.

Myth:

Uranium mining and milling activities disperse radioactive dust into the atmosphere and contaminate large areas of land and the air we breathe.

Fact:

Mining activities are safe for the health of people and the environment and generate only small quantities of local dust, which are kept to minimal levels using various methods.

Since uranium dust is heavy, it does not travel very far in air. As a result, dust concentrations in the air always remain low and are entirely contained within mine and mill sites.

Myth:

Data on the environmental performance of uranium mines and processing activities is secret and controlled by industry.

Fact:

Data on the facilities' environmental performance is collected in an annual report available on the CNSC website. The current operators of Northern Saskatchewan also routinely post their environmental monitoring data on their websites, and report their findings to the northern communities.

Contact us directly to obtained a more thorough and complex annual reports for each facility.

Myth:

Today's uranium mining and processing activities will place a heavy burden on future generations.

Fact:

The CNSC requires facility operators to maintain adequate financial guarantees to cover cleanup and monitoring of sites during operations and after they are closed.

A financial guarantee is an important condition of a CNSC licence, and the CNSC would never grant a licence to a uranium mining or processing company without one.

In addition, the CNSC reviews proposed activities to reduce the overall footprint of activities and ensure progressive remediation.

Cleanup is conducted at all stages of mining and milling.

Myth:

The transport of uranium concentrates is a dangerous activity.

Fact:

Uranium that leaves a uranium mill is not a dangerously radioactive substance.

Also known as yellowcake, it is not soluble in water and it can easily be recovered in case of a spill.

Industrial and medical applications

Myth:

Food irradiation causes the food to become radioactive.

Fact:

Food irradiation does not make food radioactive. The process involves exposing food to ionizing radiation to kill bacteria, viruses and insects in order to prevent food poisoning and spoilage. Irradiation is also used to slow ripening and sprouting in fresh fruits or vegetables. Read more about food irradiation on the website of the Canadian Food Inspection Agency.

General

Myth:

Old smoke detectors are considered nuclear waste and must be disposed of in a radioactive waste repository.

Fact:

You can dispose of your household smoke detectors in regular municipal household garbage. The tiny amount of radiation that can be measured outside the unit does not pose any risk to public health or to the environment. Read the CNSC fact sheet on smoke detector safety and disposal.

Myth:

Canada's nuclear energy sector is secretive.

Fact:

As part of its regulatory activities, the CNSC holds frequent public hearing and meetings that allow the public to learn about nuclear facilities and projects and to participate to the regulatory process as intervener. Public proceedings are available by webcast and the documentation available to the public. Read more about the work of the Commission or contact us for more details about how to get involved.